/*
 * Created on Sep 1, 2003 
 * Copyright (C) Azureus Software, Inc, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package org.gudy.azureus2.core3.disk.impl.piecemapper.impl;

import java.util.List;

import org.gudy.azureus2.core3.disk.impl.piecemapper.DMPieceList;
import org.gudy.azureus2.core3.disk.impl.piecemapper.DMPieceMapEntry;

/**
 * @author Moti
 * 
 *         PieceList contains a list of pieces; it also provides accessor and utility methods.
 */
public class PieceListImpl implements DMPieceList {

    final private PieceMapEntryImpl[] pieces;
    final private int[] cumulativeLengths;

    static public PieceListImpl convert(List pieceList) {
        return new PieceListImpl((PieceMapEntryImpl[]) pieceList.toArray(new PieceMapEntryImpl[pieceList.size()]));
    }

    protected PieceListImpl(PieceMapEntryImpl[] _pieces) {
        pieces = _pieces;
        cumulativeLengths = new int[pieces.length];

        initializeCumulativeLengths();
    }

    private void initializeCumulativeLengths() {
        int runningLength = 0;
        for (int i = 0; i < pieces.length; i++) {
            runningLength += pieces[i].getLength();
            cumulativeLengths[i] = runningLength;
        }
    }

    public int size() {
        return pieces.length;
    }

    public DMPieceMapEntry get(int index) {
        return pieces[index];
    }

    public int getCumulativeLengthToPiece(int index) {
        return cumulativeLengths[index];
    }
}
